Portuguese monks, bound for Macao, landed in Nagasaki due to bad weather, bringing sugar and changing Japan's food. Nagasaki's strong foreign trade led to a love for sweets, giving rise to treats like castella, a pound cake with Japanese twists like mizuame syrup. Fukusaya, a famous cake shop chain, offers classic castella in colorful packaging. The European influence on Japanese sweets extends to treats like dorayaki and macarons with local flavors.